TY - JOUR
T1 - Solid-state electrochemical kinetics of Li-ion intercalation into Li1-xCoO2
T2 - simultaneous application of electroanalytical techniques SSCV, PITT, and EIS
AU - Levi, M. D.
AU - Salitra, G.
AU - Markovsky, B.
AU - Teller, H.
AU - Aurbach, D.
AU - Heider, Udo
AU - Heider, Lilia
PY - 1999/4
Y1 - 1999/4
N2 - The electroanalytical behavior of thin Li1-xCoO2 electrodes is elucidated by the simultaneous application of three electroanalytical techniques: slow-scan-rate cyclic voltammetry (SSCV), potentiostatic intermittent titration technique, and electrochemical impedance spectroscopy. The data were treated within the framework of a simple model expressed by a Frumkin-type sorption isotherm. The experimental SSCV curves were well described by an equation combining such an isotherm with the Butler-Volmer equation for slow interfacial Li-ion transfer. The apparent attraction constant was -4.2, which is characteristic of a quasi-equilibrium, first-order phase transition. Impedance spectra reflected a process with the following steps: Li+ ion migration in solution, Li+ ion migration through surface films, strongly potential-dependent charge-transfer resistance, solid-state Li+ diffusion, and accumulation of the intercalants into the host materials. An excellent fit was found between these spectra and an equivalent circuit, including a Voigt-type analog (Li+ migration through multilayer surface films and charge transfer) in series with a finite-length Warburg-type element (Li+ solid-state diffusion), and a capacitor (Li accumulation). In this paper, we compare the solid-state diffusion time constants and the differential intercalation capacities obtained by the three electroanalytical techniques.
AB - The electroanalytical behavior of thin Li1-xCoO2 electrodes is elucidated by the simultaneous application of three electroanalytical techniques: slow-scan-rate cyclic voltammetry (SSCV), potentiostatic intermittent titration technique, and electrochemical impedance spectroscopy. The data were treated within the framework of a simple model expressed by a Frumkin-type sorption isotherm. The experimental SSCV curves were well described by an equation combining such an isotherm with the Butler-Volmer equation for slow interfacial Li-ion transfer. The apparent attraction constant was -4.2, which is characteristic of a quasi-equilibrium, first-order phase transition. Impedance spectra reflected a process with the following steps: Li+ ion migration in solution, Li+ ion migration through surface films, strongly potential-dependent charge-transfer resistance, solid-state Li+ diffusion, and accumulation of the intercalants into the host materials. An excellent fit was found between these spectra and an equivalent circuit, including a Voigt-type analog (Li+ migration through multilayer surface films and charge transfer) in series with a finite-length Warburg-type element (Li+ solid-state diffusion), and a capacitor (Li accumulation). In this paper, we compare the solid-state diffusion time constants and the differential intercalation capacities obtained by the three electroanalytical techniques.
UR - http://www.scopus.com/inward/record.url?scp=0032658566&partnerID=8YFLogxK
U2 - 10.1149/1.1391759
DO - 10.1149/1.1391759
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
AN - SCOPUS:0032658566
SN - 0013-4651
VL - 146
SP - 1279
EP - 1289
JO - Journal of the Electrochemical Society
JF - Journal of the Electrochemical Society
IS - 4
ER -